STAINING THE COOP ?'S

[smallflock]

My little chicken tractor is made for just 2-4 birds. It's made from pine and at it's base is 3.5 feet wide, tapering up to the roof as a triangle shape that reaches about 5.5 ft high.
The bottom is caged with an open run area and ladder that raises at night to keep the girls upstairs.
the upstairs has some roosts and at each end a nesting box. The ends open at the top to reach in to the nesting boxes, and then the whole side lifts for when you need to clean.
The bottom run area also opens at one end, and has a roost pole down there too.
The girls have learned to come upstairs at dusk when the solar light comes on upstairs and then I raise the ladder to keep them there, safe from any dogs, cats or critters that lurk in the night and might get thru the caged area underneath if they're determined enough!
So... with that little bit of coop design info I need help with two issues:
1- Can you use any kind of stain on the pine lumber that the whole tractor is made out of? And when I do stain it, how long should I keep the girls out of it?
2- This summer I'm afraid the top may get too hot, even though it has some vented areas. Will a little fan in that little area, 6.5 x 2.5 x 2.5, stir up too much dust and stuff?
Help me... LOL I've really gotten attached to these girlies!

 

[Cetawin]

A little fan will help move air through the coop and cool it down...angle it so that is does not kick up a lot of dust and you should be fine.

You can use a waterproof stain on the outside like Thompson's Waterseal. I would leave the inside plain or prime and paint it.